Luminaire photoelectric control device with reflective shield

ABSTRACT

Adjustable reflective shield member is attached to photoelectric control unit mounted in luminaire for directing to the light sensor therein ambient light from desired direction and of desired intensity.

United States Patent H 13,5s4,22s

(72] Inventors Lewis W. Kenyon [50] Field of Search 250/237, Flat Rock; 239,229, 230, 238, 105, 108; 95/10; 356/215, Robert F. Kilpatrick, Hendersonville, both 220, 22] 225; 350/266, 269, 270, 276, 277279 of, N.C. [21] Appl. No. 811,064 [56] References Cited [22] Filed Mar. 27, 1969 UNITED STATES PATENTS [45] Patented June 8, 1971 3,274,392 9/1966 Harling 250/239X [731 Ass'gnee Cmnpany 3,341,71 1 9/1967 Shephard 250/239 FOREIGN PATENTS 505,195 5/1939 Great Britain 356/225 Primary Examiner-Roy Lake H Assistant Examiner-E. R. LaRoche [54] LUMINAIRE PHOTOELECTRIC CONTROL Attorneys-Sidney Greenberg, .l. Wesley Haubner, Frank L.

Neuhauser and Oscar 3 Claims, 4 Drawing Figs.

[52] U.S. Cl 250/230, ABSTRACT: Adjustable reflective shield member is attached 250/239, 356/225 t0 photoelectric control unit mounted in luminaire for direct- [51] Int. Cl G0ld 5/30, ing to the light sensor therein ambient light from desired 9 H0 1 j 39/02 direction and of desired intensity.

PATENTED JUN 8 IQYI iiiillh LUMINAIRE PHOTOELECTRIC CONTROL DEVICE WITH REFLECTIVE SHIELD The present invention relates to illuminating devices such as outdoor luminaires and photoelectric control devices associated therewith.

It is an object of the present invention to provide luminaires of the above type with photoelectric control devices having improved light control means associated therewith.

It is another object of the invention to provide an improved light-directing device in combination with photoelectric control units for obtaining desired response of the control units to particular ambient light conditions.

A particular object of the invention is to provide a combined light-shielding and -reflecting device for photoelectric control units for selectively directing desired ambient light rays to the photoelectric control unit.

Another object of the invention is to provide a simple, inexpensive, easily assembled light shield of the above type which is readily adjustable to direct ambient light rays of desired direction and intensity to the photoelectric control unit.

Other objects and advantages will become apparent from the following description and the appended claims.

With the above objects in view, the present invention relates in one of its aspects to a luminaire having a housing, a photoelectric control unit mounted in the housing for controlling the operation of the luminaire and having a tubular portion projecting exteriorly of the housing, and a reflective member adjustably secured at the exterior end of the tubular portion and arranged to selectively direct ambient light rays into the photoelectric control unit through the tubular portion thereof.

The invention will be better understood from the following description taken in conjunction with the accompanying drawing, in which:

HO. 1 is an elevational view of a luminaire in which the invention is embodied;

FIG. 2 is an enlarged detail view, partly in section, of a portion of the FIG. 1 luminaire showing the photoelectric control unit and light-directing shield associated therewith;

FIG. 3 is an exploded view of the assembly of photoelectric control unit and light-directing shield therefor; and

FIG. 4 is a perspective view of the lightdirecting shield per Referring now to the drawing, and particularly to FIG. I, there is shown a luminaire I mounted by means of slipfitter 8 on top of support post 2 and comprising a spherical globe 3 enclosing lamp 4 and associated electrical operating components therefor, including photoelectric control unit 5. The latter unit, which may be of conventional type, comprises a housing 6 in which is contained a photoelectric cell 7 (see FIG. 2) which may be a well-known type comprising a lightsensitive material such as cadmium sulfide to which electrical leads are attached in known manner for controlling the operation of a relay and switch means (not shown), and thereby controlling the operation of lamp 4 in accordance with the intensity of ambient light incident on the photoelectric cell 7. By such control, lamp 4 may be turned on and ofl in accordance with different ambient light levels. Housing 6 is formed with a tubular portion 6a projecting outwardly therefrom with its axis aligned with the axis of photoelectric cell 7, and with the photoelectric control unit mounted in operative position in luminaire 1, tube 6a thereof projects outwardly through an aperture 8a in slipfitter 8. Adjacent its outer end, tube 6a is provided with a window or lens 6b closing the tube (see FIG. 3). To hold control unit Sin position on the luminaire, knurled nut 9 threadably engages the threaded exterior end portion of tube 611, and when tightened, nut 9 firmly clamps control unit 5 to slipfitter 8.

With the photoelectric control unit 5 so arranged in fixed position and in the absence of the light-directing shield of the invention, light-sensitive cell 7 is exposed and responsive only to entering light rays directly aligned with the axis of housing tube 6a, with the result that the response of the control unit is not adjustable to meet the conditions of the particular environment of the individual luminaire. Various conditions, such as the presence of nearby luminaires, brightly illuminated signs, headlights of an approaching vehicle, and light reflection from pools of water, highly reflecting walls and ground fog, may result in improper operation of the control unit.

In accordance with the invention, a simple and inexpensive device is provided which is readily attached to the photocontrol unit to enable a wide range of adjustment of the control unit to meet varying light conditions. FIG. 4 shows an embodiment of such a device, which comprises a combined light reflector and shield 10 formed of a metal strip, such as aluminum, bent in an angle so as to form a mounting arm portion I00 having an aperture therein and a reflector-shield portion or arm 10b arranged at an angle thereto. Shield 10 is assembled in operative position on control unit 5 as shown in FIG. 3 with the aperture in mounting arm 10a fitting over tube 6a and arm 10a lying flat against the outer surface of slipfitter 8, and knurled nut 9 is tightened on the end of tube 6a to clamp the parts in assembly as shown in FIG. 2. Shield portion 10b is readily bendable about its juncture with arm 1011, as seen in HO. 2, so as to be movable relative to the exterior end of photocontrol tube 6a to thereby vary the amount of light directed into the tube by varying the amount of shielding from no shielding to almost complete shielding of the photocontrol tube from outside ambient light. Moreover, shield 10 may be rotatably adjusted on tube 611 merely by loosening nut 9, turning shield 10 about the axis of tube 6a (as indicated by the arrow in FIG. 3) to the desired position, and retightening nut 9. Such rotational adjustment enables shield device 10 to selectively direct light rays from any direction into photoelectric control unit 5 while blocking entrance of light rays from other directions. By a combination of such rotational adjustment and bending adjustment of shield portion 10b relative to the entrance of tube 6a, a change in the direction of light sensing coupled with a change in the ambient light level required to actuate the photocontrol unit is readily achieved.

The inner surface of shield portion 10b from which incident light rays are directed into photocontrol unit 5 may, if desired, be a specular reflecting surface or may be somewhat diffusing such as results in mill-finished aluminum. In the latter case,

the surface will allow the photocontrol unit to be exposed to a fairly large area and integrate the light coming from that general direction, thus providing, forexample, reduced sensitivity to small, bright light sources such as vehicle headlights, while still affording good sensitivity to overall ambient light conditions.

The reflecting portion 10b may have other configurations than that shown; for example, it may be convex or concave, rather than flat, to afford desired light sensitivity or selective direction of actuating light rays.

It will be also understood'that the reflecting shield device of the invention may be mounted relative to the photocontrol unit in arrangements other than that shown. For example, the photocontrol unit may be of the type which is exteriorly mounted on a luminaire housing or the like and may have a projecting rim or other means on which the shield device is suitably adjustably secured in operative position. In other cases, the photocontrol unit may be mounted entirely within the luminaire housing facing a transparent window in the housing, and in such cases, the shield device may be suitably adjustably attached to the housing window for directing exterior light therethrough toward the photocontrol unit.

While the present invention has been described with reference to particular embodiments thereof, it will be understood that numerous modifications may be made by those skilled in the art without actually departing from the scope of the invention. Accordingly, we wish to have it understood that we intend herein to cover all such modifications as fall within the true spirit and scope of our invention.

What we claim as new and desire to secure by Letters Patent of the United States is:

l. A luminaire comprising, in combination, a luminaire enclosure having a wall portion formed with an aperture, a light source mounted within said enclosure, a photoelectric control unit mounted in said enclosure for controlling the operation of said light source comprising a housing containing a light-sensitive element and formed with an opening through which light rays may enter for incidence on said light-sensitive element, said photoelectric control unit being arranged with the opening in said housing aligned with said aperture in said luminaire wall portion, a combined light shield and reflecting device arranged externally of said luminaire enclosure for directing ambient light rays from a selected direction into said housing opening, said combined device comprising a bendable strip having a reflecting surface facing said opening at an angle, said strip being bendable for adjusting said reflecting surface at a selected angle relative to the axis of said opening, and means mounting said combined device on the exterior of said luminaire enclosure wall portion for selective rotational adjustment about the axis of said opening, whereby said combined device may be bendably and rotationally adjusted for selectively directing ambient light rays from predetermined directions and of predetermined intensity into said photoelectric control unit.

2. A luminaire as defined in claim 1, said strip being formed of two arms arranged at an angle to one another, one of said arms being secured to said housing adjacent said opening therein, the other arm having said reflecting surface thereon.

3. A luminaire as defined in claim 2, said mounting means comprising a tubular member projecting from said housing exteriorly through said luminaire wall aperture, said one arm of said strip being formed with an aperture for fitting over said tubular member, and clamp means 'adjustably secured to said tubular member for clamping said one arm to said luminaire wall portion. 

1. A luminaire comprising, in combination, a luminaire enclosure having a wall portion formed with an aperture, a light source mounted within said enclosure, a photoelectric control unit mounted in said enclosure for controlling the operation of said light source comprising a housing containing a light-sensitive element and formed with an opening through which light rays may enter for incidence on said light-sensitive element, said photoelectric control unit being arranged with the opening in said housing aligned with said aperture in said luminaire wall portion, a combined light shield and reflecting device arranged externally of said luminaire enclosure for directing ambient light rays from a selected direction into said housing opening, said combined device comprising a bendable strip having a reflecting surface facing said opening at an angle, said strip being bendable for adjusting said reflecting surface at a selected angle relative to the axis of said opening, and means mounting said combined device on the exterior of said luminaire enclosure wall portion for selective rotational adjustment about the axis of said opening, whereby said combined device may be bendably and rotationally adjusted for selectively directing ambient light rays from predetermined directions and of predetermined intensity into said photoelectric control unit.
 2. A luminaire as defined in claim 1, said strip being formed of two arms arranged at an angle to one another, one of said arms being secured to said housing adjacent said opening therein, the other arm having said reflecting surface thereon.
 3. A luminaire as defined in claim 2, said mounting means comprising a tubular member projecting from said housing exteriorly through said luminaire wall aperture, said one arm of said strip being formed with an aperture for fitting over said tubular member, and clamp means adjustably secured to said tubular member for clamping said one arm to said luminaire wall portion. 